They only trun off when you manually flip the switch to the OFF position, assuming you installed the standard MC system with the reversible Jabsco pumps. You'll know the tanks/bags are full when water shoots out the overflow port on each side of the boat.

agreed. when the boat starts to pee your bag is full. depending on how your setup is plumbed, each bag may have its own overflow. also, don't worry if there is still water shooting out the side even with the pump off. my fly high sacks on my 02 (same hull as yours) swell a bit with the pressure from the pump and they will overflow a bit even when the pumps are off if they are tight and full.

i think emptying them is harder as the pump can run dry if you aren't paying attention. when we are heading back to the dock, i'll run the pump to empty for a few minutes to get the majority of the ballast out, but i'll wait till i'm idling in to start the pumps again so i can pay attention to when the bags are empty. again, yours may be different, but it helps to pay attention to which bags empty where. when the motor is off, you can also hear the pitch of the pump change when its dry.

agreed. when the boat starts to pee your bag is full. depending on how your setup is plumbed, each bag may have its own overflow. also, don't worry if there is still water shooting out the side even with the pump off. my fly high sacks on my 02 (same hull as yours) swell a bit with the pressure from the pump and they will overflow a bit even when the pumps are off if they are tight and full.

i think emptying them is harder as the pump can run dry if you aren't paying attention. when we are heading back to the dock, i'll run the pump to empty for a few minutes to get the majority of the ballast out, but i'll wait till i'm idling in to start the pumps again so i can pay attention to when the bags are empty. again, yours may be different, but it helps to pay attention to which bags empty where. when the motor is off, you can also hear the pitch of the pump change when its dry.

I Like that idea of waiting till i am idling at the ramp to empty...thanks

i'm not sure of your exact setup. my setup is one through hull fitting that feeds a manifold (common weak link of that era). from the manifold, there are 3 hoses that feed 3 separate jabsco puppy pumps which feed the port and starboard lockers and ski locker bag. my rear bags have the aftermarket quick connects where my keel bag is stock and has the OEM oetiker clamps. i bought my boat used so i don't know if this is your setup. my through hull is under the hull near the paddle wheel.

probably the first thing i'd do is make sure you visualize the entire system and understand the the direction of flow of water. you've checked the impeller which is a great place to start. if you feel that the middle pump sounds different, then i'd think it may be running dry. if i'm not paying attention to my discharge holes when i'm emptying the ballast, i can tell when its empty when the pitch of the pump changes indicating its running dry. check that the flow of water is unrestricted to and from the pump. you may also have a hole in the ski locker sack. when mine is "tick" full, it will weep air/water through some of the seams. someday i'll replace it with a custom sack from wakemakers.

if your lines a long enough, you could try to swap the fill line for your ski bag to a pump you know works.

I spent some time sunday tracing all the lines to and from the manifold and tanks/bag. got the lay of the land as it were now. I had a little water on top of the bag in the keel on saturday but a little water came over the bow when a friend was driving and I was wakesurfing...amateur driver in a hurry LOL...first time driving the boat with ballast full...

checked to flow of everything...looked good except for port locker.

I did read on some other thread that the port and starboard locker pumps run better when the KGB is already running..anytruth to that Jafo?